http://ijaems.com/ Open Access international Journal to publish research paper en-us September 2020 In this work, the influence of addition of nickel and chromium micron/nano particles on the tribological behavior of developed Al6061 hybrid metal matrix composites has been identified. In the first category Al6061 based hybrid metal matrix composite reinforced with x wt.% of nickel (x=0, 0.9, 1.8 and 2.7) and same wt.% of chromium micron size particles were fabricated throughcost- effective stir casting technique. In the second category Al6061 based hybrid nano metal matrix composites reinforced with y wt.% of nickel(y=0, 0.6 and 1.2) and same wt.% of chromium nanoparticles developed through same technique. Graphite and magnesium micron/nano size particles added to improve self-lubrication property and wettability respectively. The wear rate of developed composites has been tested on pin-on-disc experimental set up at defined speed 500 RPM, sliding distance 1000 m and variable load 10N, 20N & 30N. The reduction of wear rate of Al6061/1.8Ni/1.8Cr hybrid metal matrix composite and Al6061/0.6Ninp/0.6Crnp hybrid nano metal matrix composite 37.1% and 76% w.r.to Al6061 alloy. The results revealed that there is significant improvement in wear resistance or decrement in wear rate of hybrid nano metal matrix compositesas compared to hybrid metal matrix composite and Al6061 alloy. An attempt made in this work to provide information for superior tribological behavior of hybrid nano metal matrix composites. http://ijaems.com/detail/enhancing-the-tribological-behavior-of-hybrid-al6061-metal-matrix-composites-through-the-incorporation-of-nickel-and-chromium-nanoparticles/ Raj Kumar, Dr. Dinesh Shringi, Kedar Narayan Bairwa http://ijaems.com/upload_images/issue_files/1IJAEMS-10820209-Enhancing.pdf Ensuring the environmental safety of aircraft engines is an important task for developers. This problem is becoming more urgent due to an increase in engine power, since an increase in power is achieved primarily by increasing the temperature in the combustion chamber, leading to an increase in NOx emissions. In this study, the problem of emission in the aviation industry and ways to solve it were considered. Separately, the method of reducing emissions by changing the design of combustion chambers was considered in more detail. http://ijaems.com/detail/review-of-gas-turbine-combustion-chamber-designs-to-reduce-emissions/ Fawzi Shnain Alnasur, Raheem Dohan Owayez, Khaldoon Hussein Hamzah http://ijaems.com/upload_images/issue_files/2IJAEMS-108202010-Review.pdf Due to the very high nonlinearity of the power system, traditional analytical methods take a lot of time to solve, causing delay in decision-making. Therefore, quickly detecting power system instability helps the control system to make timely decisions become the key factor to ensure stable operation of the power system. Power system stability identification encounters large data set size problem. The need is to select representative variables as input variables for the identifier. This paper proposes to apply wrapper method to select variables. In which, Binary Particle Swarm Optimization (BPSO) algorithm combines with K-NN (K=1) identifier to search for good set of variables. It is named BPSO&1-NN. Test results on IEEE 39-bus diagram show that the proposed method achieves the goal of reducing variables with high accuracy. http://ijaems.com/detail/bpso-1-nn-algorithm-based-variable-selection-for-power-system-stability-identification/ N. N. Au, V. V. Cuong, T. T. Giang, L. T. Nghia, T. V. Hien http://ijaems.com/upload_images/issue_files/3IJAEMS-10920204-BPSO.pdf The chemical separation is used to reduce the quantity of potentially toxic or hazardous materials discharged to the environment. In addition, separations that lead to recycle, recovery, or reuse of materials also prevent discharge. It is can assists in resolving some of the environmental challenges, so it became more important for researchers, in particular, environmental specialists. Hence, this article aimed to collection information about the chemical separation to help the researchers to resolve the environmental problems. Overall, it can concluded that the extraction is the first step to separate the desired substance from the raw materials and there are various methods for extraction such as sublimation, distillation method and solvent extraction. Correspondently, there are many types of separation processes, the most widely used method is the chromatography method. http://ijaems.com/detail/review-of-the-chemical-separation/ Mokhtar Mohamedalamin Mokhtar, Jianfeng Li, Zhiping Du, Fangqin Cheng http://ijaems.com/upload_images/issue_files/4IJAEMS-109202012-Reviewof.pdf